Burner constructions for hot blast stoves



y 20, 1965 H. SCHNEIDER ETAL 3,195,872

BURNER CONSTRUCTIONS FOR HOT BLAST STOVES Filed Feb. 4, 1963 2 Sheets-Sheetl M M if/4,41% ATTORNEYS y 20, 1965 H. SCHNEIDER ETAL 3,195,872

BURNER GONSTRUCTIQNS FOR HOT BLAST STOVES Filed Feb. 4, 1963 2 Sheets-Sheet? FIG.6 14

INVENTORS f/E/IVZ SCH/VE/DER LUDW/G WALT/ 5Q BY pf aim-Q M ATTORNEYS United States Patent Ofi ice 3,195,872 Patented July 20, 1965 3,195,872 BURNER CQNSTRUCTIONS FOR HOT BLAST STOVES Heinz Schneider and Ludwig Walther, Duren, Rhineland,

Germany, assignors to Zimmermann & Jansen Gesellschaft rnit heschrankter Haftung, Dnren, Rhineiand,

Germany, a corporation of Germany Filed Feb. 4, 1963, Ser. No. 255,793 12 Claims. (Cl. 26319) The present invention relates generally to hot blast stoves for blast furnaces or the like, and particularly to burners for hot blast stoves.

In prior art hot blast stoves, the combustion gas and the combustion air are supplied through separate conduits to a burner head at the combustion chamber of the blast stove, Where they are mixed. In order to efiect a good mixture of the gas and air, the conduits are usually provided with special terminal conformations. When the hot blast stove is in the ON BLAST condition, extremely high temperatures are generated in the combustion chamber, and the burner head and output terminals of the gas and air conduits are subjected thereto. As a result, the burner head and the associated output terminals must be protected against the high temperatures. This requires that they be fabricated from special heatresistant metals such as relatively expensive steel alloys. Moreover, since separate conduits are used for the air and the gas, there resulted the necessity for the use of a relatively complicated and expensive burner shut-off valve which could operate in both conduits for controlling the passage of the air and gas to the hot blast stove. In order to effect such control, the valve had to be placed forwardly of the burner head in the direction of flow of the air and the gas so that the burner head was interposed between the blast stove and the shut-off valve therefor, and subjected directly to the high blast temperatures.

In View of the foregoing, it is an object of the present invention to obviate the foregoing disadvantages of the prior art.

It is another object of the present invention to provide a construction wherein the burner head is protected from the high temperatures generated during the ON BLAST condition of the hot blast stove.

It is another object of the present invention to provide a construction wherein the burner shut-off valve can be interposed between the hot blast stove and the burner head.

It is still another object of the present invention to provide a construction which eliminates the necessity for the utilization of a relatively complex burner shut-off valve and which permits for the use of a burner shut-off valve of generally simplified construction.

It is a further object of the present invention to provide a burner head which can be fabricated from relatively inexpensive sheet metal.

It is a still further object of the present invention to provide a highly novel and efiicient burner head which effects a superior mixture of the combustion gas with the combustion air.

Other and further objects and advantages of the present invention will be readily apparent to those skilled in the art from a consideration of the following specification taken in connection with the appended drawings.

In the drawings which illustrate the best modes presently contemplated for carrying out the invention:

FIG. 1 is a more or less schematic or diagrammatic representation of a hot blast stove provided with a burner head pursuant to the present invention;

FIG. 2 is a sectional view, on an enlarged scale, taken on line 2-2 of FIG. 1;

FIG. 3 is a sectional view taken on the line 3-3 of FIG. 2;

FIG. 4 is a fragmentary detail, on an enlarged scale, of the burner head;

FIG. 5 is a perspective view of another embodiment of a burner, pursuant to the present invention, viewing the outlet end thereof, the gas conduit being omitted; and

P16. 6 is a sectional view taken on the line 66 of FIG. 5, including the gas conduit.

Referring now to FIGS. 1-4 of the drawings, in detail, there is shown a hot blast stove 10 of the type illustrated and described in United States Patent No. 3,039,522, dated June 19, 19.62, and assigned to the assignee hereof. Said stove is adapted to be heated so that it may subsequently have air passed therethrough in order to supply hot blast to a blast furnace as described in United States Patent No. 2,931,635, dated April 5, 1960, and assigned to the assignee hereof. The stove 10 is provided with a combustion chamber 12 into which a suitable combustion mixture of gas and air is introduced through a conduit 14. Gas for the combustion mixture is supplied through the gas main 16, as shown by arrow 18, and air for the combustion mixture is supplied through the air main 20, as shown by the arrow 22. The output end 24 of the air main is inserted into the gas main, as best illustrated in FIG. 1, the output end of the gas main being indicated by the reference numeral 26.

A burner 28 is interposed between the outlet end 26 of the gas main 15 and the conduit 14. The latter is connected to the combustion chamber, by means of an adaptor conduit section 30.

Pursuant to a feature of the present invention, a burner head 32 is provided at the outlet end 24 of the air conduit 26 and extends into the burner 28. As hereinafter explained in detail, the burner head 32 provides an intimate mixture of the combustion gas and the combustion air which is supplied to the combustion chamber. The burner 28 is provided with a burner shut-oif valve 34. Valve 34 is provided with an operating member or fluidflow shut-off means 36 which, in the operative condition of the valve, extends into the burner 28 and serves to close the latter to prevent the flow .of the gas-air mixture therethrough from the burner head 32. It will .be understood that in the inoperative condition of the valve, the valve closure member 36 oiiers no impediment to the flow of the combustion mixture through the burner. The closure member need not be a complex element since it is not used, as in the prior art, to close separate gas and air conduits. On the contrary, since the burner 28 is in the form of a single conduit section, the closure member 36 therefore is consequently of a simplified construction. The closure member 36 is formed of a heat resistant material and serves, in the closed or operative condition thereof, both as a shut-oil element to cut off the supply of the combustion mixture to the stove 10 as well as a heat shield when the stove is ON BLAST. As a shield, the closure element is interposed between the stoveand the burner head 32 to protect the latter from the high temperatures generated in the stove when ON BLAST. As a result, the burner head need not be formed of relatively expensive heat resistant alloy steel or similar special material.

Pursuant to the present invention, the burner head 32 is formed of a suitable sheet metal, preferably non-alloy steel, which is less expensive than the heat resistant material used in the prior art and which, consequently, permits for more flexibility in the design thereof. As here shown, the burner head 32 comprises a tubular body portion 38 which is mounted coaxially within the gas main 16 so as to define an outer passageway 40, between the outer surface of said tubular body portion and the inner surface of the gas main. Passageway 40 serves as the gas flow channel through which the gas flows-to theburner, as shown by arrow 13 in FIG. 3. The tubular body portion, per se, constitutes a passageway for air flow toward the burner,'as indicated by arrow. 22. for an intimate mixture of the gas flow along the exterior of tube 33 and the air flow. along the interior thereof so. as to blend the gas and air into a proper combustion mixstreams for interaction with-the air flowstreams emanating from the outlets 194 to provide for a superior mix- In order to provide ture, the tu'oeis provided at itsoutlet end with mixing 56 of the tubular. element 38 to define a firstseries of circumferentially spacedguidechannels 58 and a second series of circumferentially spaced guide channels 69 which are interposed between the channels '58. Channels 58 and 60 all extend in a direction oblique'to the axis of ture of the air and gas.

In view of the foregoing, it will be apparent that in both of the illustrated embodiments the gas flow and the air flow is each broken up into a plurality-of separate streams which are then intermingled with each other to provide the combustion mixture.

Whilethere'has been illustrated and described the presently preferred embodiments of. the invention, it, will be understood that various changes and modifications can be made therein without departing from the basic inventive concept thereof, as set forth in the appended claims.

Having thus described our'invention, what we claim and desire to secure by Letters Patent is: V

' 1. Afburner headicomprising a firstjtubular member provided with mixing conformations formed at one end thereof and defining a first fluid flow path, a second tubular member surrounding the 'first'tubulaii member and defining with the first tubular member a second fluid 1 fiow path,'said mixing conformations comprising a first tubular element 38 with channels 58 being directe'dradially inwardly of said tubular element and channel 60 being 7 directed radially outwardly thereof. Each channel 58 is provided with an entrance or inlet 62 within the gas passageway 49 so as to direct-the gas'flow inwardly from said passageway into air flowing through the burner head a between the outer surface of the inner tube 44 and the inner surface of .the tube 3%, as indicated by arrow 64.

A baffle 66 disposed in each channel 58 is provided with deflectors 68 and 70 which break up the gas flow therethrough into separate streams, as indicated at72and 74, so as to facilitate the mixture thereof with the rotary air streams flowing through out of tube 44. .Each

channel 60 has an entrance 76 in the ,air' flow path between the outer surface of inner tube 44,and1the inner surface of the outer tube 38, so asto direct air outwardly from thev passageway therebetween into the gas 1 flow passageway between the outer surface of tube 32 and the inner surface of conduit 16 A bafiie 78 disposed ineach series of elongated guide channels having inlet ends located within the first tubular member and outlet ends located in the second fluid flow pathfand'directing fluid from the second series'of elongated guide channels having inlet ends located between the 'first'and second tubular members and outlet ends located in the first fluid flow path and directing fluid from the second fluid flow path into the first fluid flow path.- V r 2, A burner head as in claim 1, said guide channels of said first seriesinterposed between the guide channels of .said second series.

' 3. A burner headers in claim 1, and baflle means provided within each of saidiguide channels for directing the streams in the guide channels into separate predetermined flow directions.

f 4. A burner as in claim 1, said burner head having channel 60 is provided with deflectors 80 and 82 which break up the airflow .therethrough into separate streams,

as indicated at 84 and 86, so as to facilitate themixture thereof with the gas fiow' streamfabout the"tube 38.

Consequently, it will be apparent that due to the'various guidelchannels and battles which 'breakfup the air and a gas into a multiplicity of differently directed streams which then interact with each other a highly superior gas 50 air combustion mixture is achieved.

Referring now to FIGS/5 and 6, there is shown amodified burner'head88 mounted within the gas conduit 16. Burnerhead 88 is also formed of a suitable sheet metal, preferably non-alloy steel, andcomprises a tubular body portionr9tl which is mounted coaxiallywithin the,

gas main 16 so as to define anouter passageway 92 between the outer' surface of tube 90 and the inner surface of the gas main. channel through which the. gasfflowsto the burner as shown by arrow 94. The interior of tube 90 serves as the air flow passageway, as indicated by arrow 96. At'its Passageway 92 serves as the gas flow means to effect a rotary movement of the streams from 5. A burner head as defined in claim 1, said burner head having means coaxially disposed with respect to, and adjacent, the end of the firsttubular memberpsaid means hav ng swirl fins to provide av rotary movement to a portion of said first flow path.

6. A burner head as defined in claim 1, said first series of channels being formedwith means defining jet outlets.

7. A burner. head' as defined in claim 1, said second series of guide channels'having bafiies which extend towards the axis of saidfirst'tubular member.

8. A burner head as defined in claim 6, said second T series of guide {channels havingbaffies which extend towards, thea'xis of said first tubular member.

9. In. a hot blast stove adapted to be heated and to supply hot blast toa blast furnace, gas conduit means for supplying gas to said stove, airconduit means for supplying an tosaid stove, one of said'conduit means having an outletportion disposed coaxially within the other of'said conduit means, gas air mixing means provided on said coaxially disposed outlet portion and comprising a first series of elongated guide channels having inlet-ends located outlet end, tube'9t) is'provided with the radially spaced inwardly directed'integral baflies 98 whichareinterposed between circumferentially spaced guide channels 100 defined by integral conformation 102 provided on the 104 for channels 109. baflles 98 andthe conformations 102 theairflow through the tube 90 is broken up into a plurality or jet-like air 106 therebetwe'en which are defined also by the baflies 98 therebetween. Said channels serve as guide channels for the gas flow and break the latter up into separate tube 90. Said conformations define triangular outlets It Willbe apparent that due to the 7 [directing fluid from the gas conduit into the path of the air fro m the air conduit. r

within the airconduit and outlet ends located in'the path of the gas from the gas conduit and directing fluid from the aircon'duit into the path of the gas from the gas conduit, and a second series of elongated guide channels having' inlet ends located in the gas conduit-and outlet ends located in'the path of the air from. the air conduit and 10. A hot blast stove as set forth in claim 9, saidone conduit means being an air conduit and the said other conduit means being a'gas conduit.

11; A hot blast stove assetforth in claim 9, including valve means provided in said other conduit means between 5 6 said mixing means and said stove, said valve means being 2,627,307 2/53 Westling 158-109 operable when the stove is on blast to Sh t Off the gas-air 2,713,894 7/55 Sage 15 8118 X mixture from said stove and to protect said mixing means from the heat of said stove. FOREIGN PATENTS 12. A blast stove as in claim 9, said guide channels 5 515,109 11/20 France.

having means for forming the gas and air in the said 917,802 9/46 Fran e, guide channels into a plurality of separate streams. 683,439 11/39 Germany.

References Cited by the Examiner OTHER REFERENCES UNITED STATES PATENTS 10 German printed application No. 1,050,007, printed 1,713,313 5/29 Willcox 26319 ebmary 1959' 1,760,050 5/30 Eickworth 158-118X 1963009 6/34 Wunsch 158-109 FREDERICK L. MATTESON, JR., Przmary Examiner. 1,963,010 6/34 Wunsch 158109 15 MEYER PERLIN, JAMES W. WESTHAVER,

2,090,771 8/37 Whitcomb 158109 Examiners. 

1. A BURNER HEAD COMPRISING A FIRST TUBULAR MEMBER PROVIDED WITH MIXING CONFORMATIONS FORMED AT ONE END THEREOF AND DEFINING A FIRST FLUIE FLOW PATH, A SECOND TUBULAR MEMBER SURROUNDING THE FIRST TUBULAR MEMBER AND DEFINING WITH THE FIRST TUBULAR MEMBER A SECOND FLUID FLOW PATH, SAID MIXING CONFORMATIONS COMPRISING A FIRST SERIES OF ELONGATED GUIDE CHANNELS HAVING INLET ENDS LOCATED WITHIN THE FIRST TUBULAR MEMBER AND OUTLET ENDS LOCATED IN THE SECOND FLUID FLOW PATH AND DIRECTING FLUID FROM THE FIRST FLUID FLOW PATH INTO THE SECOND FLUID FLOW PATH, AND A SECOND SERIES OF ELONGATED GUIDE CHANNELS HAVING INLET ENDS LOCATED BETWEEN THE FIRST AND SECOND TUBULAR MEMBERS AND OUTLET ENDS LOCATED IN THE FIRST FLUID FLOW PATH AND DIRECTING FLUID FROM THE SECOND FLUID FLOW PATH INTO THE FIRST FLUID FLOW PATH. 